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Einstein's riddle

Einstein's riddle

They say that when Einstein proposed this puzzle he said that 98% of the world's population would not be able to solve it. Will you get it?

We have 5 houses of five different colors. In each of them lives a person of a different nationality and each of the owners drinks a different drink, smokes a different brand of cigarettes and has a different pet.

They tell us the following:
1.- English lives in the Red house
2.- The Swedish pet is a dog
3.- Danish drinks tea
4.- The green house is the immediate one to the left of the white house
5.- The owner of the green house drinks coffee
6.- The person who smokes Pall mall raises birds
7.- The owner of the yellow house smokes Dunhill
8.- The man who lives in the center house drinks milk
9.- The Norwegian lives in the first house
10.-The person who smokes Blend lives next to the one who has cats
11.-The man who has horses lives next to the one who smokes Dunhill
12.-The person who smokes blue Masters drinks beer
13.-The German smokes Prince
14.-The Norwegian lives next to the blue house
15.-The man who smokes Blend has a neighbor who drinks water

Who has the fish tank?

Solution

You will find the solution very well explained on this page.

The best way to solve these types of problems is to draw a table in which we mark the information we have and discard the options that are impossible.

In this case we could start with the following table in which we have included the direct data provided by the problem:

HousePetDrinkCigarette brand
BritishRed???
Swedish?Dog??
Danish??Tea?
Norwegian????
German???Prince

According to the problem data we can reach the following conclusions:

The Norwegian lives in the first house, therefore he does not live in the middle house and therefore does not drink milk. As tea is drunk by the Danish Norwegian, there is only coffee, beer or water left.

Since the Norwegian lives in the first house, he has no other left, so he does not live in the green, he also lives next to the blue house and as the British lives in the red, the Norwegian is left with the white or yellow .

We add this data to the table:

HousePetDrinkCigarette brand
BritishRed???
Swedish?Dog??
Danish??Tea?
NorwegianWhite
Yellow
?Coffee
Beer
Water
?
German???Prince

The owner of the green house drinks coffee, therefore it is not the Danish that can only live in a white, yellow or blue house, we also put it on the table and for the same reason the Norwegian does not drink coffee so we also remove this possibility .

HousePetDrinkCigarette brand
BritishRed???
Swedish?Dog??
DanishWhite
Yellow
blue
?Tea?
NorwegianWhite
Yellow
?Beer
Water
?
German???Prince

From the phrase "The owner of the green house drinks coffee" and since we know that the Danish drinks tea, the British can only drink milk, beer or water.

According to the phrase "The owner of the yellow house smokes Dunhill" the British can only smoke Pall Mall, Brends or Bluemasters.

Updating the table with this information would look like this:

HousePetDrinkCigarette brand
BritishRed?Milk
Beer
Water
pall Mall
Brends
Bluemasters
Swedish?Dog??
DanishWhite
Yellow
blue
?Tea?
NorwegianWhite
Yellow
?Beer
Water
?
German???Prince

We know that whoever smokes Bluemasters drinks beer, therefore Danish by not drinking beer does not smoke either Bluemasters, nor prince, has Pall Mall, Dunhill or Brends.

The one who smokes Bluemasters drinks beer, therefore the German does not drink beer or tea, he has coffee, milk or water.

We update the table with this new information:

HousePetDrinkCigarette brand
BritishRed?Milk
Beer
Water
pall Mall
Brends
Bluemasters
Swedish?Dog??
DanishWhite
Yellow
blue
?Teapall Mall
Dunhill
Brends
NorwegianWhite
Yellow
?Beer
Water
?
German??Coffee
Milk
Water
Prince

The person who smokes Pall Mall has a bird so the German does not have a bird or a dog, it has a cat, horse or fish.

The Swede has a dog therefore neither smokes Pall Mall nor Prince, he has Dunhill, Brends and Bluemasters.

HousePetDrinkCigarette brand
BritishRed?Milk
Beer
Water
pall Mall
Brends
Bluemasters
Swedish?Dog?Dunhill
Brends
Bluemasters
DanishWhite
Yellow
blue
?Teapall Mall
Dunhill
Brends
NorwegianWhite
Yellow
?Beer
Water
?
German?Cat
Horse
Little fish
Coffee
Milk
Water
Prince

The owner of the yellow house smokes Dunhill therefore he is not the German, he has the green, white or blue house.

The Norwegian lives in the first house and is either white or yellow, in addition the green house is to the left of the white, so the white cannot be the first, therefore the Norwegian lives in the yellow.

Since the Norwegian is the one who lives in the yellow, the Danish can only live either in the white or in the blue.

Besides, now that we know that Norwegian lives in yellow, we also know that Dunhill smokes.

The updated table looks like this:

HousePetDrinkCigarette brand
BritishRed?Milk
Beer
Water
pall Mall
Brends
Bluemasters
Swedish?Dog?Brends
Bluemasters
DanishWhite
blue
?Teapall Mall
Brends
NorwegianYellow?Beer
Water
Dunhill
GermanGreen
White
blue
Cat
Horse
Little fish
Coffee
Milk
Water
Prince

Since the red and yellow houses are already occupied the Swede lives or in the green, white or blue.

The person who has a horse lives next to the one that Dunhill smokes, therefore the Norwegian has neither horse nor dog, he has left bird, cat and little fish, but since the bird belongs to the one who smokes Pall Mall he can only have cat or little fish .

HousePetDrinkCigarette brand
BritishRed?Milk
Beer
Water
pall Mall
Brends
Bluemasters
SwedishGreen
White
blue
Dog?Brends
Bluemasters
DanishWhite
blue
?Teapall Mall
Brends
NorwegianYellowCat
Little fish
Beer
Water
Dunhill
GermanGreen
White
blue
Cat
Horse
Little fish
Coffee
Milk
Water
Prince

We change strategy and try to put the houses in order.

The Norwegian lives in the first house that is yellow and also lives next to the blue house that can only be the second.

In the house of the center (the 3) they drink milk and as in the green they drink coffee and it is to the left of the white one, the green can only be in position 4 and the white one in position 5.

The position of the houses would be:

Home 1House 2House 3House 4House 5
Yellowblue?GreenWhite
??MilkCoffee?
Norwegian????

We also put the data that we already know from the previous table.

Home 1House 2House 3House 4House 5
YellowblueRedGreenWhite
??MilkCoffee?
Norwegian?British??
Dunhill????
HousePetDrinkCigarette brandPosition
BritishRed?Milkpall Mall
Brends
Bluemasters
House 3
SwedishGreen
White
blue
Dog?Brends
Bluemasters
House 2
House 4
House 5
DanishWhite
blue
?Teapall Mall
Brends
House 2
House 4
House 5
NorwegianYellowCat
Little fish
Beer
Water
DunhillHome 1
GermanGreen
White
blue
Cat
Horse
Little fish
Coffee
Milk
Water
PrinceHouse 2
House 4
House 5

The person who has a horse lives next to the one who smokes Dunhill, therefore the horse will live in house 2 which is the blue one, since the Swede has a dog does not live in the blue house.

The owner of the green house drinks coffee therefore the Danish does not live in the house 4.

The one who smokes Bluemasters drinks beer, so the Briton does not smoke Bluemasters, and only the Swede remains.

Home 1House 2House 3House 4House 5
YellowblueRedGreenWhite
??MilkCoffee?
Norwegian?British??
Dunhill????
?Horse???
HousePetDrinkCigarette brandPosition
BritishRedBird
Cat
Little fish
Milkpall Mall
Brends
House 3
SwedishGreen
White
DogBeerBluemastersHouse 4
House 5
DanishWhite
blue
Bird
Cat
Horse
Little fish
Teapall Mall
Brends
House 2
House 5
NorwegianYellowCat
Little fish
WaterDunhillHome 1
GermanGreen
White
blue
Cat
Horse
Little fish
CoffeePrinceHouse 2
House 4
House 5

The owner of the green house drinks coffee and is German. Therefore the Swede lives in the white and the Danish in the blue.

HousePetDrinkCigarette brandPosition
BritishRedBird
Cat
Little fish
Milkpall Mall
Brends
House 3
SwedishWhiteDogBeerBluemastersHouse 4
House 5
DanishblueBird
Cat
Horse
Little fish
Teapall Mall
Brends
House 2
House 5
NorwegianYellowCat
Little fish
WaterDunhillHome 1
GermanGreenCat
Horse
Little fish
CoffeePrinceHouse 2
House 4
House 5

The green house is to the left of the white one, so the green one is 4 and the white one is 5.

The person who has a horse lives next to the one who smokes Dunhill, therefore lives in the 2.

HousePetDrinkCigarette brandPosition
BritishRedBirdMilkpall Mall
Brends
House 3
SwedishWhiteDogBeerBluemastersHouse 5
DanishblueHorseTeapall Mall
Brends
House 2
NorwegianYellowCat
Little fish
WaterDunhillHome 1
GermanGreenCat
Little fish
CoffeePrinceHouse 4

The person who smokes Pall Mall has a bird and is the British.

And finally, the person who smokes Brends lives next to the one with a cat, so we leave the table solved.

HousePetDrinkCigarette brandPosition
BritishRedBirdMilkpall MallHouse 3
SwedishWhiteDogBeerBluemastersHouse 5
DanishblueHorseTeaBrendsHouse 2
NorwegianYellowCatWaterDunhillHome 1
GermanGreenLittle fishCoffeePrinceHouse 4

Solution to the puzzle of Eistein.

THE GERMAN HAS A PET FISH.